Magnetoencephalographic (MEG) brain activity during a mental flexibility task suggests some shared neurobiology in children with neurodevelopmental disorders

Cerebral blood flow in attention deficit hyperactivity disorder: A systematic review

BACKGROUND AND OBJECTIVES

Attention deficit hyperactivity disorder (ADHD) is one of the most frequent and disabling neurodevelopmental disorders. Recent research on cerebral blood flow (CBF) has enhanced understanding of the underlying pathophysiology in neuropsychiatric disorders. This systematic review aims to synthesize the existing literature on CBF anomalies among individuals with ADHD in comparison to controls.

METHODS

Following the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) approach, a systematic literature search was conducted using PubMed, PsycInfo, and Web of Science to identify relevant studies on CBF in ADHD.

RESULTS

Twenty studies, encompassing a total of 1652 participants with ADHD and 580 controls, were included, employing measurements from SPECT (n = 9), ASL (n = 6), PET (n = 4), and BOLD-derived quantitative maps (n = 1). In individuals with ADHD during resting state, hypoperfusion was frequently observed in the right orbitofrontal gyrus, temporal cortex, basal ganglia and putamen. Conversely, hyperperfusion was noted in frontal lobes, left postcentral gyrus, and occipital lobes. During cognitive tasks, hyperperfusion was observed in frontal areas, temporal regions, cingulate cortex and the precuneus. Furthermore, the administration of methylphenidate was associated with increased CBF in striatal and posterior periventricular regions, the right thalamus, and the precentral gyrus.

CONCLUSION

This review highlights diverse CBF anomalies in ADHD. The most consistently reported findings suggest hypoperfusion during resting state in prefrontal and temporal areas, along with the basal ganglia, while there is a hyperperfusion in frontal, parietal and occipital regions. Further research, including longitudinal studies, is essential to develop a comprehensive understanding of CBF implications in ADHD.

Dorsal Striatal Functional Connectivity and Repetitive Behavior Dimensions in Children and Youths With Neurodevelopmental Disorders

BACKGROUND

Impairing repetitive behaviors are one of the core diagnostic symptoms in autism spectrum disorder and obsessive-compulsive disorder, but they also manifest in attention-deficit/hyperactivity disorder. Although the dorsal striatal circuit has been implicated in repetitive behaviors, extensive heterogeneity in and cross-diagnostic manifestations of these behaviors have suggested phenotypic and likely neurobiological heterogeneity across neurodevelopmental disorders (NDDs).

METHODS

Intrinsic dorsal striatal functional connectivity was examined in 3 NDDs (autism spectrum disorder, obsessive-compulsive disorder, and attention-deficit/hyperactivity disorder) and typically developing control participants in a large single-cohort sample (N = 412). To learn how diagnostic labels and overlapping behaviors manifest in dorsal striatal functional connectivity measured with functional magnetic resonance imaging, the main and interaction effects of diagnosis and behavior were examined in 8 models (2 seed functional connectivity [caudate and putamen] × 4 sub-behavioral domains [sameness/ritualistic, self-injury, stereotypy, and compulsions]).

RESULTS

The obsessive-compulsive disorder group demonstrated distinctive patterns in visual and visuomotor coordination regions compared with the other diagnostic groups. Lower-order repetitive behaviors (self-injury and stereotypy) manifesting across all participants were implicated in regions involved in motor and cognitive control, although the findings did not survive effects of multiple comparisons, suggesting heterogeneity in these behavioral domains. An interaction between self-injurious behavior and an attention-deficit/hyperactivity disorder diagnosis were observed on caudate-cerebellum functional connectivity.

CONCLUSIONS

These findings confirmed high heterogeneity and overlapping behavioral manifestations in NDDs and their complex underlying neural mechanisms. A call for diagnosis-free symptom measures that can capture not only observable symptoms and severity across NDDs but also the underlying functions and motivations of such behaviors across diagnoses is needed.

Preliminary Observations of Resting-State Magnetoencephalography in Nonmedicated Children with Obsessive-Compulsive Disorder

Background: Cortico-striato-thalamo-cortical (CSTC) network alterations are hypothesized to contribute to symptoms of obsessive-compulsive disorder (OCD). To date, very few studies have examined whether CSTC network alterations are present in children with OCD, who are medication naive. Medication-naive pediatric imaging samples may be optimal to study neural correlates of illness and identify brain-based markers, given the proximity to illness onset. Methods: Magnetoencephalography (MEG) data were analyzed at rest, in 18 medication-naive children with OCD (M = 12.1 years ±2.0 standard deviation [SD]; 10 M/8 F) and 13 typically developing children (M = 12.3 years ±2.2 SD; 6 M/7 F). Whole-brain MEG-derived resting-state functional connectivity (rs-fc), for alpha- and gamma-band frequencies were compared between OCD and typically developing (control) groups. Results: Increased MEG-derived rs-fc across alpha- and gamma-band frequencies was found in the OCD group compared to the control group. Increased MEG-derived rs-fc at alpha-band frequencies was evident across a number of regions within the CSTC circuitry and beyond, including the cerebellum and limbic regions. Increased MEG-derived rs-fc at gamma-band frequencies was restricted to the frontal and temporal cortices. Conclusions: This MEG study provides preliminary evidence of altered alpha and gamma networks, at rest, in medication-naive children with OCD. These results support prior findings pointing to the relevance of CSTC circuitry in pediatric OCD and further support accumulating evidence of altered connectivity between regions that extend beyond this network, including the cerebellum and limbic regions. Given the substantial portion of children and youth whose OCD symptoms do not respond to conventional treatments, our findings have implications for future treatment innovation research aiming to target and track whether brain patterns associated with having OCD may change with treatment and/or predict treatment response.

Flights and Perchings of the BrainMind: A Temporospatial Approach to Psychotherapy

This article introduces a process-oriented approach for improving present moment conceptualization in psychotherapy that is in alignment with neuroscience: the Temporospatial movements of mind (TSMM) model. We elaborate on seven temporal movements that describe the moment-to-moment morphogenesis of emotional feelings and thoughts from inception to maturity. Temporal refers to the passage of time through which feelings and thoughts develop, and electromagnetic activity, that among other responsibilities, bind information across time. Spatial dynamics extend from an undifferentiated to three dimensional experiences of emotional and cognitive processes. Neurophysiologically, spatial refers to structures within the brain and their varying interactions with one another. This article culminates in the development of an atheoretical temporospatial grid that may help clinicians conceptualize where patients are in their cognitive and emotional development to further guide technique.

The Performance of Visual, Auditory, and Motor Cognitive Flexibility for Children with Autism Spectrum Disorder in Taiwan

PURPOSE

Few studies have tested the cognitive flexibility, specifically auditory and motor flexibility of children with ASD. This study was conducted to understand the relationship between cognitive flexibility and visual, auditory, and motor development in young children with ASD and autistic behaviors.

PARTICIPANTS AND METHODS

A purposive sampling approach was used to screen nineteen four- to five-year-old ASD children. Tests included the Autism Behavior Checklist-Taiwan Version and Cognitive Flexibility Test, which included visual, auditory, and motor cognitive flexibility subtests.

RESULTS

At the pre-switch and post-switch of three subtests, there were considerable variations in the number of ASD passing. According to the findings, children aged five had more visual cognitive flexibility than children aged four, but the lack of significant differences for the other flexibilities. The negative correlation of the three cognitive flexibilities with autistic behaviors was -0.57~-0.64.

CONCLUSION

Children with ASD have significant difficulties in switching rule tasks characterized by visual, auditory, and motor cognitive flexibility. The results suggest that visual cognitive flexibility had an age effect. The negative correlation of the three cognitive flexibilities with autistic behaviors was moderate.

Cognitive and behavioural flexibility: neural mechanisms and clinical considerations

Cognitive and behavioural flexibility permit the appropriate adjustment of thoughts and behaviours in response to changing environmental demands. Brain mechanisms enabling flexibility have been examined using non-invasive neuroimaging and behavioural approaches in humans alongside pharmacological and lesion studies in animals. This work has identified large-scale functional brain networks encompassing lateral and orbital frontoparietal, midcingulo-insular and frontostriatal regions that support flexibility across the lifespan. Flexibility can be compromised in early-life neurodevelopmental disorders, clinical conditions that emerge during adolescence and late-life dementias. We critically evaluate evidence for the enhancement of flexibility through cognitive training, physical activity and bilingual experience.

Visuomotor Activation of Inhibition-Processing in Pediatric Obsessive Compulsive Disorder: A Magnetoencephalography Study

Background: Response inhibition engages the cortico-striato-thalamo-cortical (CSTC) circuit, which has been implicated in children, and youth with obsessive compulsive disorder (OCD). This study explored whether CSTC engagement during response inhibition, measured using magnetoencephalography (MEG), differed in a sample of medication-naïve youth with OCD, compared to typically developing controls (TDC). Methods: Data was analyzed in 17 medication-naïve children and youth with OCD (11.7 ± 2.2 SD years) and 13 TDC (12.6 ± 2.2 SD years). MEG was used to localize and characterize neural activity during a Go/No-Go task. Task performance on Go/No-Go conditions and regional differences in amplitude of activity during Go and No-Go condition between OCD vs. TDC were examined using two-sample t-tests. Post-hoc analysis with Bayesian t-tests was used to estimate the certainty of outcomes. Results: No differences in Go/No-Go performance were found between OCD and TDC groups. In response to the visual cue presented during the Go condition, participants with OCD showed significantly increased amplitude of activity in the primary motor (MI) cortex compared to TDC. In addition, significantly reduced amplitude of PCu was found following successful stopping to No-Go cues in OCD vs. TDC during No-Go task performance. Bayesian t-tests indicated high probability and large effect sizes for the differences in MI and PCu amplitude found between groups. Conclusion: Our preliminary study in a small medication-naïve sample extends previous work indicating intact response inhibition in pediatric OCD. While altered neural response in the current study was found during response inhibition performance in OCD, differences localized to regions outside of the CSTC. Our findings suggest that additional imaging research in medication-naïve samples is needed to clarify regional differences associated with OCD vs. influenced by medication effects, and suggest that MEG may be sensitive to detecting such differences.